I HC QUC GIA TP H CH MINH TRNG I HC CNG NGH THNG TIN KHOA KHOA HC MY TNH N TT NGHIP TI: TM HIU FUZZY ONTOLOGY V FUZZY-OWL Gio vin hng dn:ThS. TRNG HI BNG Sinh vin thc hin:TRN THANH TON PHM NH N Lp:KHOA HC MY TNH Kha:01 TP.H CH MINH, 5-2010M U Vic biu din tri thc v Lp Lun L vn then cht cho qu trnh x L thng tin t ng trong cc h thng thng minh. Trong thi gian gn y, mt vn quan trng v ang c nhiu nh nghin cu quan tm L biu din v x L tri thc trn Web. Nm 1998, Tim Berners-Lee nghin cu v pht trin Semantic web (web ng ngha),theocchnycctrangwebkhngchthchinchcnngnhnvhinth thng tin mcn c kh nng t ng trch rt thng tin, truy vn, Lp Luntrong c s tri thc c th cho ra cc thng tin mt cch t ng, chnh xc.Nm2003,F-BaaderphttrinLogicmt(DescriptionLogicDLs) ([11],[20],[19]) v xem n nh L ngn ngbiu din tri thc trn web ng ngha. T vic nghin cu qu trnh biu din v Lp Lun trong web ng ngha c quan tm tuy nhin ch dng Li i vi tri thc chc chn.Nm 2006, Umberto Straccia da vo nn tng ca Logic m t v L thuyt tp m ca Zadeh xy dng Logic m t m (Fuzzy Description Logic) ([9]) nhm phc v cho vic x l tri thc khng chc chn trn web ng ngha. T vic nghin cu v pht trin Logic m t m nh l mt c s cho vic biu din tri thc v lp lun c t ra. Vn then cht ca web ng ngha L xy dng cc c s tri thc (OntoLogy m) [10] t to ra c chLp Lun trn c s tri thc cho ra cc thng tin cn thit. Bi bocpvicsdngLogicmtmF-SHIN[10]choLpLuntrn(Fuzzy Ontology) [11],[19]. Trong thi gian qua em c iu kin c tip xc nghin cu v Fuzzy Ontology. T nhng nghin cu ny, trong n em s nu ln cc vn c bn ca Fuzzy Ontology v cc kin thc c lien quan. Do vy cc ni dung ca lun vn s c trnh by theo cc ni dung sau: -Chng 1. Ontology: Chng ny gii thiu mt s kin thc c bn v ontology v cc vn lin quan. Trong chng ny chng ta s tm hiu v cc thnh phn c bn ca Ontology cng nh cc bc xy dng Ontology. Cc kin thc trong phn ny kt hp vi Logic m t c gii thiu trong chng tip theo l kin thc c bn xy dng Ontology m. -Chng 2. Logic m t: y l chng gii thiu v nhng ni dung c bn ca logic m t nh khi lc v logic m t, cc ngn ng ca logic m t, kin trc ca mt h c s tri thc da trn logic m t, cc bi ton quyt nh. -Chng3.FuzzyOntologyandfuzzyOWL:ylchngtrnhbynghincu v vic s dng Logic m t m cho lp lun trn Ontology m. Trnylnhngphnchnhsctrnhbytrongn.Trnthctvncn nhiu vn cn phi tm hiu v Ontology m. Em hy vng mnh s c iu kin tip tc i su hn vo vic nghin cu ng dng ca logic m t trong thi gian ti. Cuicng,emxincgilicmncamnhtithygiohngdnthcs Trng Hi Bng du dt, h tr v gip em hon thnh ti ny. Phn trnh by caemchcchncnnhiuthiust,emrtmongcsgpcathycth hon thin tt hn ti. LI CM N ChngemxinchnthnhcmnccthyctrongkhoaKhoaHcMyTnh Trng i Hc Cng Ngh Thng Tin h tr to nhiu iu kin thun li cho chng em trong qu trnh hc tp cng nh qu trnh thc hin n tt nghip. Chng em xin ghi nhn lng bit n su sc n Th.S Trng Hi Bng l ngi trc tiphngdnemlmn.Cmnthytntnhhngdn,truyntchoem nhng kin thc qu bu em c th hon thnh n ny. Chng em cng xin chn thnh cm n qu thy c trong Khoa Khoa Hc My Tnh tntnhgingdy,trangbchochngemnhngkinthccnthittrongsutqu trnh hc tp v nghin cu ti khoa. Cui cng chng ti xin gi li cm n n bn b hi thm, ng vin v gip chng ti trong qu trnh thc hin n. Mc d chng em n lc ht sc hon thnh tt ti ca mnh nhng d sao nhng sai st trong n l nhng iu khng th trnh khi.Em rt mong nhnc s thng cm v nhng kin ng gp tntnh ca cc thy, c gio v cc bn cng nh nhng ai quan tm ti lnh vc trong n ny. Tp.H Ch Minh, ngy 30 thng 8 nm 2010 NHN XT (Ca ging vin hng dn) ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... ............................................................................................................................................... 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............................................................................................................................................... ...............................................................................................................................................MC LC CHNG 1. TNG QUAN V ONTOLOGY. ....................................................... 1 1.1.Gii thiu. .............................................................................................................. 1 1.2.Qu trnh hnh thnh. ............................................................................................. 1 1.3.Khi nim v ontology. .......................................................................................... 3 1.4.Cc phn t trong ontology. ................................................................................... 4 1.4.1.Cc c th (Individuals) Th hin. ............................................................... 4 1.4.2.Cc Lp (Classes) - Khi nim. ...................................................................... 4 1.4.3.Cc thuc tnh (Properties). ............................................................................. 5 1.4.4.Cc mi quan h (Relation). ............................................................................ 5 1.5.Phn loi: ................................................................................................................ 7 1.6.Vai tr ca Ontology. ............................................................................................. 9 1.7.Phng Php xy dng ontology. ........................................................................ 10 1.8.Ngn ng Web Ontology (OWL). ....................................................................... 15 1.9.Mt vi m hnh ontology. ................................................................................... 18 1.10.Ngn ng ontology. .......................................................................................... 19 1.11.Tng kt chng ............................................................................................... 21 CHNG 2. LOGIC M T (DESCRIPTION LOGIC) ................................... 21 2.1.Gii thiu. ............................................................................................................ 21 2.2.Ngn ng thuc tnh AL. ..................................................................................... 23 2.2.1.Ngn ng m t c bn AL. .......................................................................... 24 2.2.2.Ng ngha ca cc khi nim AL .................................................................. 24 2.2.3.H ngn ng logic m t AL. ....................................................................... 25 2.2.4.Ngn ng m t l tp con ca logic v t bc nht. ..................................... 26 2.3.H c s tri thc ................................................................................................... 27 2.3.1.Kin trc h logic m t. ............................................................................... 27 2.3.2.B thut ng (TBox) ..................................................................................... 27 FUZZY ONTOLOGY AND FUZZY OWL 1 | P a g eSVTH: Trn Thanh Ton Phm nh n 2.3.2.1.Tin thut ng .................................................................................... 28 2.3.2.2.nh ngha khi nim ............................................................................. 28 2.3.2.3.M rng b thut ng. ............................................................................ 29 2.3.2.4. quy .................................................................................................... 31 2.3.2.5.Thut ng vi cc tin bao hm......................................................... 31 2.3.3.B khng nh (ABox). ................................................................................. 32 2.3.4.C th ............................................................................................................. 33 2.3.5.Suy lun. ........................................................................................................ 34 2.3.5.1.Loi tr TBox. ........................................................................................ 35 2.3.5.2.Lp lun i vi ABox. .......................................................................... 36 2.3.5.3.Ng ngha ng, ng ngha m. ...................................................... 37 2.4.Cc thut ton suy lun. ....................................................................................... 38 2.4.1.Thut ton bao hm cu trc. ........................................................................ 38 2.4.2.Thut ton tableau. ........................................................................................ 40 2.5.M rng ngn ng m t ..................................................................................... 44 2.5.1.Cc constructor vai tr .................................................................................. 45 3.5.2.Biu din cc gii hn s .............................................................................. 45 2.6.Tng kt chng .................................................................................................. 46 CHNG 3. FUZZY ONTOLOGY AND FUZZY OWL. .................................. 46 3.1.Logic m t m. ................................................................................................... 46 3.1.1.Gii thiu. ...................................................................................................... 46 3.1.2.C php v ng ngha ca logic m t m. ................................................... 47 3.1.2.1.Ton t m. ............................................................................................ 47 3.1.2.2.Concrete Fuzzy Concepts. ...................................................................... 48 3.1.2.3.Fuzzy Numbers. ...................................................................................... 48 3.1.2.4.Truth constants. ...................................................................................... 49 3.1.2.5.Concept modifiers (b ng khi nim). .................................................. 49 3.1.2.6.Features (chc nng). ............................................................................. 49 3.1.2.7.Datatype restrictions (gii hn kiu d liu). ......................................... 49 2 | P a g e FUZZY ONTOLOGY AND FUZZY OWL GVHDThS. Trng Hi Bng 3.1.2.8.Din gii cc khi nim. ......................................................................... 50 3.1.2.9.Tin . ................................................................................................... 51 3.1.3.Mt s ngn ng logic m t m. ................................................................. 52 3.1.3.1.Logic m t m F-SHIN : ...................................................................... 52 3.1.3.1.1. C php ................................................................................................ 52 3.1.3.1.2. Ng ngha ............................................................................................. 53 3.1.3.2.Logic m t m SHOIN (D) ................................................................... 54 3.1.3.2.1. Nhc li logic m t SHOIN (D). ......................................................... 54 3.1.3.2.2. logic m t m SHOIN (D). ................................................................ 57 3.1.3.2.3. Logic m t m SROIQ. ...................................................................... 63 3.2OntoLogy m ....................................................................................................... 66 3.2.1.Nhc li nh ngha ontology. ....................................................................... 66 3.2.2.nh ngha ontology m. .............................................................................. 67 3.2.2.1.nh ngha 1. .......................................................................................... 67 3.2.2.2.nh ngha 2. .......................................................................................... 68 3.2.2.3.nh ngha 3. .......................................................................................... 70 3.2.2.4.nh ngha 4. .......................................................................................... 71 3.2.2.5.nh ngha 5. .......................................................................................... 71 3.2.2.6.nh nghia 6. .......................................................................................... 71 3.2.2.7.nh ngha 7. .......................................................................................... 72 3.2.3.Nhng li th ca fuzzy ontology. ................................................................ 74 3.2.4.C s tri thc trong ontology m. ................................................................. 75 3.3.Fuzzy OWL. ......................................................................................................... 77 CHNG 4. V D P DNG. ................................................................................ 82 DANH MC CC S , HNH Trang Hnh 1.1 Cy Brentano v cc phm tr ca Aristotle2 Hnh 1.2 Cy Porphyry2 Hnh 1.3Mt Ontology biu din quan h ca xe c.6 Hnh 1.4 Cu trc lp phn cp13 Hnh 1.5 Rng buc14 Hnh 1.6 s nh x cc thnh phn ca m hnh thc th kt hp v d liu sang ontology v th hin. 19 Hnh 1.7 kin trc logic m t.21 Hnh 2.1 Kin trc h logic m t27 Hnh 2.2 TBox vi cc khi nim v quan h gia nh29 Hnh 2.3 Khai trin TBox quan h gia nh trong Hnh30 Hnh 2.4 B khng nh (ABox)32 Hnh 2.5 ABox Aoe v cu truyn Oedipus38 Hnh 2.6 Lut bin i ca thut ton tableau gii bi ton tha43 Hnh 2.7 V d chng minh Mother Parent44 Hnh 3.1. (a) Crisp value; (b) L-function; (c) R-function; (d) (b) Triangular function; (e) Trapezoidal function; (f) Linear hedge. 48 Hnh 3.2. (a) Trapezoidal function; (b) Triangular function; (c) L-function;(d) R-function 58 Hnh 3.3 Cu trc ca mt ontology m68 Hnh 3.4 Ba lp cu trc ontology70 Hnh 3.5 S mt fuzzy ontology73 DANH SCH CC BNG Trang Bng 1.1 Cc m t thuc tnh i tng OWL15 Bng 1.2 Cc m t thuc tnh i tng OWL16 Bng 1.3 Cc tin v cc s kin ca OWL16 Bng 2.1 C php ca ngn ng AL24 Bng 2.2 Ng ngha ca logic m t25 Bng 3.1 Ton t m48 Bng 3.2 Gii hn kiu d liu.50 Bng 3.3 Din gii cc khi nim.51 Bng 3.4 Cc tin trong logic m t m.52 FUZZY ONTOLOGY AND FUZZY OWL 1 | P a g eSVTH: Trn Thanh Ton Phm nh n Bng 3.5 C php ca cc khi nim v phng thc trong F-SHIN53 Bng 3.6 Ng ngha ca cc khi nim v phng thc trong F-SHIN54 Bng3.7 m rng cc khi nim trong SHOIN(D)55 Bng 3.8 ABox, TBox v RBox trong SROIQ.64 Bng 3.9 M rng cc khi nim trong SROIQ.65 Bng 3.10 phn bit s khc nhau gia fuzzy ontology v Crisp ontology.75 Bng 3.11 S Lng gii hn m.77 Bng 3.12 Tin m79 Bng 3.13 Rng buc m80 Bng 3.14 Tin ca fuzzy OWL.81 K HIU CC CM T VIT TTOWLWeb Ontology Language CGsConceptual Graphs KIFKnowledge Interchange Format CGIFConceptual Grap Interchange Form DLsDescription logic F-OWLFuzzy OWL FUZZY ONTOLOGY AND FUZZY OWL 1 | P a g eSVTH: Trn Thanh Ton Phm nh n CHNG 1. TNG QUAN V ONTOLOGY. 1.1.Gii thiu. Chng ny gii thiu mt s kin thc c bn v ontology v cc vn lin quan. TrongnntngWebngnghami,ontologyngmtvaitrquantrngdoyl phngtingipcungcpngnghachocctrangweb.Doccnghincuv ontologycnthitchonthinphcvchonhucucachunwebmivn angthusquantmrnglntgiinghincu.Knghontologyllnhvcmi trong khoa hc my tnh v khoa hc thng tin, nghin cu cc phng php v phng phplunxydngccontology.Mctiucannhmlmrnghacctrithc cha ng trong mt lnh vc c th. K ngh ontology a ra mt phng hng nhm ti vic giiquyt ccvn hot ng tng tc xut hinbi cc ro cn ng ngha, cc ro cn lin quan n cc nh ngha ca cc thut ng hay cc khi nim. K ngh ontology l mt tp hp cc nhim v lin quan n vic pht trin cc ontology cho mt lnh vc c th. Bi ton so khp ontology l mt trong nhng nhim v nh th. 1.2.Qu trnh hnh thnh. Ontology bt ngun t Hy Lp, t ontos c ngha l s tn ti (being), t logos ngha l din t (word); c ngha l din t s tn ti. N nh hng mt thi gian trong nn trit hc ca Hy Lp. Aristotle (384-332 trc CN) gii thiu 10 phm tr c bn nm mc l ca cy hnh 1.1, cc phm tr ca ng c nh hng mnh m n cc ontology sau ny. Sau Brentano b sung cc phm tr cn li hnh thnh cy Brentano, l mt hnh thc ca ontology. 2 | P a g e FUZZY ONTOLOGY AND FUZZY OWL GVHDThS. Trng Hi Bng Hnh 1.1 Cy Brentano v cc phm tr ca Aristotle. Hnh 1.2Cy Porphyry. Mt ontology khc c bit n l cy Porphyry do trit gia Hy Lp Porphyry, sng vo th k 3 sau Cng Nguyn, v ra da trn t tng ca Ariseoele c minh ha hnh FUZZY ONTOLOGY AND FUZZY OWL 3 | P a g eSVTH: Trn Thanh Ton Phm nh n 1.2. Theo cy ny vt cht l khi nim cao nht khng th tm thy khi nim no cao hn. Cn nhn loi l khi nim thp nht, di nhn loi ch c c nhn nh: Socrates, Plato, Aristotle Bn cnh vic nh ngha cc phm tr biu din ontology, Aristotle cn xy dng nn tam on lun lm nn mng cho logic hc. 1.3.Khi nim v ontology. Theo trit hc th ontology c nh nghanh sau: ontology l mt siu hnh hc nghin cu v s tn ti v hin thn ca t nhin [Aristoteles] Theo tin hc th ontology c nhng nh ngha sau: -Gruber(1993),Ontologylmtthuytminhhnhthc,rrngcamtnhn thcchung.nhnghacangcphnlm4khinimchnh:mttru tng ca hin tng (nhn thc ), din t r rng bng ton hc (hnh thc), cc khi nim v quan h gia chng phi c nh ngha mt cch chnh xc v r rng, tn ti mt s ng thun ca nhng ngi s dng ontology (chung). -Rusell & Norving (1995), Ontology l mt m t hnh thc ca cc khi nim v quan h c th tn ti trong mt cng ng c th. -Swartout(1996),Ontologylmttpthutngccutrcvbcdint mt phm vi c th v c th c s dng nh l b khung ca c s tri thc. -Fensel (2000), Ontology l m t mt cch ph bin, c kh nng dng chung v hnh thc ca cc khi nim quan trng trong mt phm vi c th. -John F.Sowa (2000), Ontlogy l mt bn lit k cc kiu ca nhng g m tn ti trongminDtkhacnhmngisdngngnngLmtD.Cckiu ca Ontology bao gm: v t, ngha t, hay khi nim v quan h ca ngn ng L khi m t v D. -Noy & Mc.Guinness (2001), Ontology l mt m t hnh thc v r rng ca cc khinimtrongphmvicth,ccthuctnhcakhinimmtctnhv tnh cht ca khi nim, cc rng buc ca thuc tnh. -Fonseca (2002), Ontology l mt l thuyt m s dng mt b t vng c th m t thc th, thuc tnh v cc thao tc trong mt phm vi c th. -Enrico Franconi (2003), Ontology l mt nhn thc hnh thc v th gii. -Starlap(2003),Ontologybaohmccthutng,xcnhnghacavmi quan h gia chng. -A.Maedche&B.Motik&L.Stojanvic(2003),Ontologylmhnhkhinim trong phm vi ng dng nht nh, c th chia s v thc thi trn my tnh.Theo cc nh ngha trn mt Ontology phi c nhng tnh cht sau: 4 | P a g e FUZZY ONTOLOGY AND FUZZY OWL GVHDThS. Trng Hi Bng -c s dng m t mt phm vi ng dng c th. -Cc khi nim v quan h c nh ngha r rng trong phm vi ng dng . -C c ch t chc cc khi nim (thng l phn cp). -C s ng thun v mt ngha cc khi nim ca nhng ngi cng s dng ontology. 1.4.Cc phn t trong ontology. Cc ontology hin nay u c nhiu im tng t v mt cu trc, bt k ngn ng cdngbiudin.Huhtccontologyumtccitng(thhin),lp (khi nim), thuc tnh v cc quan h. 1.4.1.Cc c th (Individuals) Th hin. C th (hay th hin) l thnh phn c bn, mc nn ca mt ontology. Cc c th trongmtontologycthbaogmccitngrircnhconngi,conth,xe, nguynt,hnhtinh,trangweb,cngnhccitngtrutngnhconsvt (mc d c mt vi khc bit v kin liu cc con s v t l lp hay l i tng). Ni ngra,mtontologykhngcnchabtccthno,nhngmttrongnhngmc ch chung ca ontology l cung cp mt phng tin phn loi cc i tng, ngay c khi cc i tng ny khng phi l mt phn r rng ca ontology. 1.4.2.Cc Lp (Classes) - Khi nim. Lpkhinimcthcnhnghatheocchbnngoihaybntrong.Theo nh nghabn ngoi,chng l nhngnhm, b hoc tp hp cc i tng. Theonh nghabntrong,chnglccitngtrutngcnhnghabigitrcacc mt rng buc khin chng phi l thnh vin ca mt lp khc. Lp c th phn loi cc c th, c lp khc, hay mt t hp ca c hai. Mt s v d ca lp: -Person, lp ca tt c con ngi, hay cc i tng tru tng c th c m t bi cc tiu chun lm mt con ngi. -Vehicle, lp ca tt c xe c, hay cc i tng tru tng c th c m t bi cc tiu chun lm mt chic xe. -Car, lp ca tt c xe hi, hay cc i tng tru tng c th c m t bi cc tiu chun lm mt chic xe hi. -Class, biu din lp tt c cc lp, hay cc i tng tru tng c th c m t bi cc tiu chun lm mt lp. FUZZY ONTOLOGY AND FUZZY OWL 5 | P a g eSVTH: Trn Thanh Ton Phm nh n -Thing, biu din lp tt c mi th, hay cc i tng tru tng c th c m t bi cc tiu chun lm mt th g (v khng phi khng-l-g c). Mt lp c th gp nhiu lp hoc c gp vo lp khc; mt lp xp gp vo lp khc c gi l lp con (hay kiu con) ca lp gp (hay kiu cha). V d, Vechicle gp Car, bi v bt c th g l thnh vin ca lp sau cng u l thnh vin ca lp trc. Quan h xp gp c dng to nn mt cu trc phn cp cc lp, thng thng c mt lp tng qut ln nht chng hn Anything nm trn cng v nhng lp rt c th nh2002FordExplorernmdicng.Hqucckquantrngcaquanhxp gp l tnh k tha ca cc thuc tnh t lp cha n lp con. Do vy, bt c th g hin nhin ng vi mt lp cha cng hin nhin ng vi cc lp con ca n. Trong mt s ontology, mt lp ch c cho php c mt lp cha, nhng trong hu ht cc ontology, cc lp c cho php c mt s lng lp cha bt k v trong trng hp sau tt c cc thuc tnh hin nhinca tng lp cha c k tha bi lp con.Do mt lp c th ca lp th (HouseCat) c th l mt con ca lp Cat v cng l mt con ca lp Pet. 1.4.3.Cc thuc tnh (Properties). Ccitngtrongmtontologycthcmtbngcchlinhchngvi nhngthkhc,thnglccmthaybphn.Nhngthclinhnythng c gi l thuc tnh, mc d chng c th l nhng th c lp. Mt thuc tnh c th l mt lp hay mt c th. Kiu ca i tng v kiu ca thuc tnh xc nh kiu ca quan h gia chng. Mt quan h gia mt i tng v mt thuc tnh biu din mt s kin c th cho i tng m n c lin h. V d i tng Ford Explorer c cc thuc tnh nh: - Ford Explorer - door (vi s lng ti thiu v ti a: 4) - {4.0L engine, 4.6L engine} - 6-speed transmission Gi tr thuc tnh c th thuc kiu d liu phc; trong v d ny, ng c lin h ch c th l mt trong s cc dng con ca ng c, ch khng phi l mt ci n l. Cc ontology ch mang y ngha nu cc khi nim c lin hvi cc khi nim khc (cc khi nim u cthuc tnh). Nu khng ri vo trng hp ny, th hoc ta s c mt phn loi (nu cc quan h bao hm tn ti gia cc khi nim) hoc mt t in c kim sot. Nhng th ny u hu ch nhng khng c xem l ontology.1.4.4.Cc mi quan h (Relation). 6 | P a g e FUZZY ONTOLOGY AND FUZZY OWL GVHDThS. Trng Hi Bng Quan h gia cc i tng trong mt ontology cho bit cc i tng lin h vi i tng khc nh th no. Thng thng mt quan h l ca mt loi (hay lp) c th no ch r trong ng cnh no i tng c lin h vi i tng khc trong ontology. VdtrongontologychakhinimFordExplorervkhinimFordBroncocth c lin h bimt quan h loi . Pht biu y ca s kin nh sau: -Ford Explorer c nh ngha l mt con ca : Ford Bronco iu ny cho ta bit Explorer l m hnh thay th cho Bronco. V d ny cng minh ha rng quan h c cch pht biu trc tip. Pht biu ngc biu din cng mt s kin nhng bng mt ng nghch o trong ngn ng t nhin. Phn ln sc mnh ca ontolgy nm kh nng din t quan h. Tp hp cc quan h cng nhau m t ng ngha ca domain. Tp cc dng quan h c s dng (lp quan h) v cy phn loi th bc ca chng th hin sc mnh din t ca ngn ng dng biu din ontology. Hnh 1.3Mt Ontology biu din quan h ca xe c. asuperclass- of, hayngc li, ldngconca is-a-subtype-of hayl lp con ca is-a-subclass-of). N nh ngha i tng no c phn loi bi lp no. V d, ta thy lp Ford Explorer l lp con ca 4-Wheel Drive Car v lp 4- Wheel Drive Car li l lp con ca Car. S xut hin ca quan h l lp con ca to ra mt cu trc phn cp th bc; dng cu trc cy ny (hay tng qut hn, l tp c th t tng phn) m t r rng cch thc cc i tng lin h vi nhau. Trong cu trc ny, mi i tng l con ca mt lp cha (Mt s ngn ng gii hn quan h l lp con ca trong phm vi mt cha cho mi nt, nhng a s th khng nh th).FUZZY ONTOLOGY AND FUZZY OWL 7 | P a g eSVTH: Trn Thanh Ton Phm nh n Mt dng quan h ph bin khc l quan h meronymy, gi l b phn ca, biu din lm th no cc i tng kt hp vi nhau to nn i tng tng hp. V d, nu ta mrngontologytrongvdchathmmtskhinimnhSteeringWheel(v lng), ta s ni rng V lng c nh ngha l mt b phn ca Ford Explorer v v lnglunlunlmttrongnhngbphncaxeFordExplorer.Nuaquanheronymy vo ontology ny, ta s thy rng cu trc cy n gin v nh nhng trc s nhanh chng tr nn phc tp v cc k kh hiu. iu ny khng kh l gii; mt lp no c m t rng lun lun c mt thnh vin l b phn ca mt thnh vin thuc lp khc th lp ny cng c th c mt thnh vin l b phn ca lp th ba. Kt qu l cc lp c th l b phn ca nhiu hn mt lp. Cu trc ny c gi l th chu trnh c hng. Ngoi nhng quan h chun nh l lp con ca v c nh ngha l b phn ca, ontology thng cha thm mt s dng quan h lm trau chut hn ng ngha m chng m hnh ha. Ontology thng phn bit cc nhm quan h khc nhau. V d nhm cc nquan h v: -Quan h gia cc lp -Quan h gia cc thc th -Quan h gia mt thc th v mt lp -Quan h gia mt i tng n v mt tp hp -Quan h gia cc tp hp. Cc dng quan h i khi c th chuyn ngnh v do ch s dng lu tr cc dng s kin c th hoc tr li cho nhng loi cu hi c th. Nu nh ngha ca dng quanhcchatrongmtontologythontologynynhrangnngnhngha ontology cho chnh n. Mt v d v ontology nh ngha cc dng quan h ca chnh n v phn bit cc nhm quan h khc nhau l ontology Gellish.V d, trong lnh vc xe t, ta cn quan h c sn xut ti cho bit xe c lp rp ti ch no. Nh vy, Ford Explorer c sn xut ti Louisville. Ontology c th cngbitcLouisvilletalctiKentuckyvKentuckycnhnghalmt bang v l b phn ca Hoa K. Phn mm s dng ontology ny s c th tr li mt cu hi nh nhng xe hi no c sn xut ti Hoa K?. 1.5.Phn loi: Theo cch phn loi ca John F.Sowa, c 2 loi. 8 | P a g e FUZZY ONTOLOGY AND FUZZY OWL GVHDThS. Trng Hi Bng -Ontologyhnhthc(formalontology):lontologymtcckhinimmt cch chi tit n cc tin v nh ngha m khng quan tm n cc m t ny c thc hin d dng trn my tnh hay khng. Ontology hnh thc thng c xu hng nh, nhng cc tin v nh ngha thng rt phc tp trong suy lun v tnh ton. Nhng ontology ny thng do cc nh trit hc thit k. -Ontology thut ng (terminological ontology): l ontology m t cc khi nim theohngtinvnhnghacphtbiudnglogichoctrongmtvi ngn ng hng i tng chomytnhthc hin vic chuyni theo dng logic.Dnglogicnykhngcshnchvvicphtbiucctinvnh ngha v cho my tnh thc hin dng. Cc tin v nh ngha ch m t n cc vn mngdng quan tm.Ontology thut ng ln nhngcc tin v nhnghathngrtddngtrongsuylunvtnhton.Nhngontologyny thng do cc nh tin hc thit k. Theo cch phn loi ca D.Fensel, c 7 loi: -Knowledge Representation ontology: da trn cc cch biu din tri thc truyn thng. V d: Frame-Ontology. -General/Common ontology: T vng lin quan nmi th, skin, thigian, khng gian, V d: ontology v bng trao i gia meter v inch. -Meta-ontology: nh ngha cc ontology. V d: Registry Ontology, dng qun l cc ontology khc. -Domain ontology: t vng ca cc khi nim trong mt phm vi. V d: ontology v l thuyt hoc cc nguyn l c bn ca mt min. -Task ontology: h thng cc t vng ca cc thut ng gii quyt cc vn kthplinquannnhimvmcthcnghockhngcngphmving dng c th. V d: ontology v k hoch phn cng nhim v. -Domain-taskontology:taskontologycsdnglitrongmtngdngc th. V d: ontology v phn cng nhim v ca cc chuyn bay. -Application ontology: cha cc kin thc cn thit ca mt ng dng trong phm vi ng dng nht nh. V d: ontology hnh hc. FUZZY ONTOLOGY AND FUZZY OWL 9 | P a g eSVTH: Trn Thanh Ton Phm nh n 1.6.Vai tr ca Ontology. Vi ngha v cu trc nh trn, Ontology tr thnh mt cng c quan trng trong lnh vc Web ng ngha. C th k ra mt s li ch ca Ontology nh:- chia s nhng hiu hiu bit chung v cc khi nim, cu trc thng tin gia con ngi hoc gia cc h thng phn mm: y l vai tr quan trng nht ca mtOntology,khngnhngtronglnhvcWebngnghamcntrongnhiu ngnhvlnhvckhc.Vphngdinny,cthhnhdungOntologyging nhmtcuntinchuynngnh,cungcpvgiithchccthutngcho ngi khng c cng chuyn mn khi c yu cu. Khng ch c s dng bi con ngi, Ontology cn hu ch khi cn s hp tc gia cc h thng phn mm. Lyvd,OpenBiologicallbOntologynitingcphttrinbitrng i hc Stanford nhm cung cp cc thut ng mt cch y trong ngnh sinh vthc.OntologynyhinctchhpvomtsngdngWebtrn Internet.Sau,mtphnmmtracuhocdysinhhctrnmytnhcth kt ni vi cc ng dng Web trn ly thng tin cho mc tiu ch gii.-Cho php ti s dng tri thc: y l mt vn kh v l mc tiu nghin cu quantrngtrongnhngnmgny.Nlinquannbitontrnhaihay nhiuOntologythnhmtOntologylnvyhn.Nhngvnyl tncckhinimcnhnghatrongccOntologynycthgingnhau trong khi chng c dng m t cc loi vt hon ton khc nhau. Tuy nhin cng c th c trng hp ngc li, khi tn cc khi nim khc nhau nhng cng m t mt s vt. Ngoi ra, lm th no b sung cc quan h, thuc tnh c sn vo mt h thng mi cng lm cho vn tr nn phc tp.-Chophptrithcclpvingnng:ycnglvnlinquannlnh vc ti s dng tri thc ni trn, tuy nhin bi ton ca n l lm th no mt h thng Ontology c th c dng bi cc ngn ng ca cc quc gia khc nhaumkhng phixydng li. Giiphpm Ontologymangli l chophp tn cc khi nim v quan h trong Ontology mi tham kho cc khi nim, nh ngha camt h thng Ontology chun thng c xy dng bng ting Anh. iu ny c th s ph v phn no ro cn v mt ngn ng khi m kt qu tm kimskhngbgntrongtkhavngnngmnsdng.Ngoira, Ontology c th s tr thnh hng i mi cho mt lnh vc quen thuc l dch ti liu t ng. C th ni nh vy, bi ng ngha cc t vng trong vn bn s c dch chnh xc hn khi c nh x vo ng ng cnh ca n.-Chophptrithctrnnnhtqunvtngminh:cckhinimkhcnhau trongmthaynhiulnhvccthcthcngtnvgynhpnhngvng 10 | P a g e FUZZY ONTOLOGY AND FUZZY OWL GVHDThS. Trng Hi Bng ngha, tuy nhin khi c a vo mt h thng Ontology th tn mi khi nim l duy nht. Mt gii php cho vn ny l Ontology s s dng cc tham kho URI lm nh danh tht s cho khi nim trong khi vn s dng cc nhn gi nh bn trn thun tin cho ngi dng.-Cungcpmtphngtinchocngvicmhnhha:Ontologylmttpcc khi nim phn cp c lin kt vi nhau bi cc quan h. C bn mi khi nim cthxemnhlmtlp,mitngcalpcngccquanhgp phn to nn cu trc ca bi ton hay vn cn gii quyt.-Cungcpmtphngtinchovicsuylun:hinnay,mtsngnng OntologytchhplpOntologysuylun(OntologyInferenceLayer)bn trongchomcchsuylunlogictrntpquanhgiaccitngtrongh thng.1.7.Phng Php xy dng ontology. C nhiu phng php khc nhau xy dng mt Ontology, nhng nhn chung cc phng php u thc hin hai bc c bn l: xy dng cu trc lp phn cp v nh ngha cc thuc tnh cho lp. Trong thc t, vic pht trin mt Ontology m t min cnquantmlmtcngvickhngngin,phthucrtnhiuvocngcs dng, tnh cht, quy m, s thng xuyn bin i ca min cng nh cc quan h phc tp trong . Nhng kh khn ny i hi cng vic xy dng Ontology phi l mt qu trnh lp i lp li, mi ln lp ci thin v tinh ch dn sn phm ch khng phi l mt quy trnh khung vi cc cng on tch ri nhau.Ngoira,cngvicxydngOntologycngcnphitnhnkhnngmrng min quan tm trong tng lai, kh nng k tha cc h thng Ontology c sn, cng nh tnhlinhngOntologyckhnngmtttnhtccquanhphctptrongth giithc.Nidungchngnyscpnmtsnguyntccbncavicxy dng Ontology qua cc cc cng on cth sau y (Quy trnh pht trin gm 7 bc doStanfordCenterforBiomedicalInformaticsResearchara,ylhmphttrin phn mm Protg trnh din v xon tho Ontology ):-Xc nh min quan tm v phm vi ca Ontology.-Xem xt vic k tha cc Ontology c sn.-Lit k cc thut ng quan trng trong Ontology.-Xy dng cc lp v cu trc lp phn cp.-nh ngha cc thuc tnh v quan h cho lp.-nh ngha cc rng buc v thuc tnh v quan h ca lp.FUZZY ONTOLOGY AND FUZZY OWL 11 | P a g eSVTH: Trn Thanh Ton Phm nh n -To cc thc th cho lp.Bc 1: Xc nh min quan tm v phm vi ca Ontology. Gingnhmicngonctkhc,ctOntologybtubngvictrli nhng cu hi mang tnh phn tch nhn din chnh xc cc yu cu. Thng thng, cc yu cu i vi mt h thng Ontology l m t min quan tm nhm phc v c s trithctrongvicgiiquytnhngmcchchuynbit.Do,nhngcuhiny thng l:-Ontology cn m t min no?-Ontology phc v cho mc ch chuyn bit g?-C s tri thc trong Ontology s tr li nhng cu hi g?-Ontology nhm vc v i tng no?-Ai l ngi s xy dng, qun tr Ontology?Nhnchung,cutrlichocccuhidngnycthsthngxuynthayi trong sut qu trnh lp xy dng mt Ontology. Nht l khi c s thay i v mc ch hoccnbsungtnhnngtrongvicsdngcstrithc.Tuynhin,victrli chnh xc cc cu hi trn ti mi bc lp s gip gii hn phm vi thc s ca m hnh cn m t v d tr cc k thut s s dng trong qu trnh pht trin. Ly v d, nu d tr kh nng xy ra s khc bit v ngn ng gia ngi pht trin v ngi s dng th Ontology phi c b sung c ch nh x (mapping) qua li cc thut ng gia cc ngn ngkhcnhau.HocgisOntologycnxydngcchcnngxlngnngt nhin, ng dng dch ti liu t ng th cng cn thit phi c k thut xc nh t ng ngha chng hn. Sau khi pht tho phm vi Ontology da trn vic tr li nhng cu hi trn, ngi thit k s tr li cc cu hi mang tnh nh gi, qua tip tc tinh chnh li phm vi cahthngcnxydng.Cccuhidngnythngdatrncstrithcca Ontology v c gi l cu hi kim chng kh nng (competency question):-Ontology c thng tin tr li cho cc cu hi c quan tm trn c s tri thc hay khng?-Cu tr li ca c s tri thc p ng c mc , yu cu no ca ngi s dng?-Cc rng buc v quan h phc tp trong min quan tm c biu din hp l cha?Bc 2: Xem xt vic k tha cc Ontology c sn 12 | P a g e FUZZY ONTOLOGY AND FUZZY OWL GVHDThS. Trng Hi Bng ylmtcngonthnghaysdnggimthiucngscxydngmt Ontology. Bng cch k tha cc Ontology tng t c sn, ngi xy dng c th thm hocbtcclp,quanhgiacclp,thcth..tinhchnhtytheomcchca mnh.Ngoira,vicsdngliccOntologycsncngrtquantrngkhicns tng tc gia cc ng dng khc nhau. L do l cc ng dng s cn phi hiu cc lp, thc th, quan h.. ca nhau thun tin trong vic trao i hoc thng nht thng tin. Vn xy dng mt Ontology mi bng cch k tha cc h thng c sn lin quan nmtbitonrtphctpltrn(merging)ccOntology.Nhnitrongmc trc, tn cc khi nim c nh ngha trong cc Ontology ny c th ging nhau trong khi chng c dng m t cc loi vt hon ton khc nhau. Trong khi , cng c th xy ra trng hp ngc li, khi tn cc khi nim khc nhau nhng cng m t mt s vt. V mt vn na l lm th no b sung cc quan h, thuc tnh c sn vo mt h thng mi. Tuy nhin, hu ht cc Ontology s dng trong ngnh khoa hc my tnhnichungvWebngnghaniringucxydngtrncchthngxy dngvquntrOntology.Cthktnmtscngc,chnghn:Sesame,Protg, Ontolingua, Chimaera, OntoEdit, OidEd.. Hin nay, a s cc phn mm ny u h tr chc nng t ng trn cc Ontology cng hoc thm ch khc nh dng vi nhau. Mc dvy,mcno,ngixydngcngcnphikimtralimtcchthcng, nhng y c l cng khng phi l mt cng vic phc tp.Hin c rt nhiu Ontology c chia s trn Web. C th k ra mt s Ontology ni ting nh: UNSPSC (www.unspsc.org) do Chng trnh pht trin ca Lin Hip Quc hp tc vi t chc Dun & Bradstreet nhm cung cp cc thut ng ca cc sn phm v dchvthngmi.CcOntologytronglnhvcthngmikhcnh:RosettaNet (www.rosettanet.org),DMOZ(www.dmoz.org),eClassOwl,..OpenBiological,BioPax tronglnhvcsinhvthc,UMLStronglnhvcmngngngha,GO(Gene Ontology), WordNet (i hc Princeton).. Bc 3: Lit k cc thut ng quan trng trong Ontology. Ontology c xy dng trn c s cc khi nim trong mt lnh vc c th, v vy khi xy dng ontology cn bt u t cc thut ng chuyn ngnh xy dng thnh cc lptrongontologytngng.Ttnhinkhngphithutngnocngavo ontology,vchachcnhvcchothutng.Docnphilitkcc thut ng, xc nh ng ngha cho cc thut ng , cng nh cn nhc v phm vi ca ontology. Vic lit k cc thut ng cncho thyc phn no tng quan v cc khi nim trong lnh vc , gip cho cc bc tip theo c thun li. Bc 4: Xc nh cc lp v phn cp ca cc lp. FUZZY ONTOLOGY AND FUZZY OWL 13 | P a g eSVTH: Trn Thanh Ton Phm nh n Hnh 1.4: Cu trc lp phn cp Cngvicxcnhcclpkhng chnginltinhnhtmhiuv ngnghacaccthutngc ccccmtchothutng, mcnphinhvchocclpmi, loi b ra khi ontology nu nm ngoi phm vi ca ontology hay hp nht vi cclpcnucnhiuthutng cngnghanhnhau(ngngha, hay a ngn ng). Ngoi ra khng phi thut ng no cng mang tnh cht nh mt lp. Mtcngviccnphitinhnh song song vi vic xc nh cc lp l xc nh phn cp ca cc lp . Vic ny gip nh v cc lp d dng hn. C mt s phng php tip cn trong vic xc nh phn cp ca cc lp: -Phng php t trn xung (top-down):bt u vi nh ngha ca cc lp tng qutnhttronglnhvcvsauchuynbithacckhinim.Vd: Trong Ontology v qun l nhn s, ta bt u vi lp Ngi, sau chuyn bit ha lp Ngi bng cch to ra cc lp con ca lp Ngi nh : K s, Cng nhn, Bc s, Lp K s cng c th chuyn bit ha bng cch to ra cc lp con nh K s CNTT, K s in, K s c kh, -Phng php t di ln (bottom-up): bt u vi nh ngha ca cc lp c th nht,nhccltrongcyphncp.Saugpcclplithnhcckhi tngquthn.Vd:tabtuvivicnhnghacclpnh:nhnvinl tn, nhn vin v sinh, nhn vin k thut. Sau to ra mt lp chung hn cho cc lp l lp nhn vin. -Phngphpkthp:kthpgiaphngphpttrnxungvtdiln: btutnhnghacclpdthytrcvsautngquthavchuyn bit ha cc lp mt cch thch hp. V d ta bt u vi lp nhn vin trc, l thut ng hay gp nht trong qun l nhn s. Sau chng ta c th chuyn bit ha thnh cc lp con: nhn vin l tn, nhn vin v sinh, hoc tng qut ha ln thnh lp Ngi. Bc 5: nh ngha cc thuc tnh v quan h cho lp:. Lp gc Lp trung gian Lp l 14 | P a g e FUZZY ONTOLOGY AND FUZZY OWL GVHDThS. Trng Hi Bng Hnh 1.5: Rng buc Bnthncclpnhncbctrnchmilnhngthutngphnbitvi nhaubngtngi.Vcbn,chngchaphcvchovicbiudintrithc. Munnhvy,ccthuctnhcalpcncnhngha.Thuctnhcalplcc thng tin bn trong ca lp, m t mt kha cnh no ca lp v c dng phn bit vi cc lp khc. Thuc tnh c chia lm nhiu loi khc nhau:-Vmtngha,ccthuctnhcthcchialmhailoi:thuctnhbn trong(intrinsicproperty)vthuctnhbnngoi(extrinsicproperty).Thuc tnh bn trong m t cc tnh cht ni ti bn trong s vt, v d: cht, lng, cu to..Trongkhi,thuctnhbnngoimtphnbiuhincasvt,vd: mu sc, hnh dng..-V mt gi tr, cc thuc tnh cng c chia lm hai loi: thuc tnh n (simple property)vthuctnhphc(complexproperty).Thuctnhnlccgitr n v d: chui, s..,cn thuc tnh phc c th cha hoc tham kho n mt i tng khc.Mt ch quan trng na trong bc ny l vic mt lp s k tha ton b cc thuc tnh ca tt c cc cha n. Do , cn phi xem xt mt thuc tnh c nh ngha cc lp thuc mc cao hn hay cha. Thuc tnh ch nn c nh ngha khi n l tnh cht ring ca lp ang xt m khng c biu hin cc lp cao hn.Bc 6: nh ngha cc rng buc v thuc tnh v quan h ca lp. Cc rng buc gii hn gi tr mmtthuctnhcthnhn. Hairngbucquantrngnht ivimtthuctnhllng s(cardinality)vkiu(type). Rngbuclngsquynhs gitrmmtthuctnhcth nhn. Hai gi tr thng thy ca rngbucnylntr(single) v a tr (multiple). Nhng mt s phn mm cn cho php nh ngha chnh xc khong gi tr ca lng s. Rng buc th hai l v kiu. V cbn, cckiummt thuctnh c th nhnl: chui, s, boolean, lit k v kiu thc th. Ring kiu thc th c lin quan n hai khi nim gi l: min (domain) vkhong(range).Khinimmincdngchlp(haycclp)mmtthuc tnh thuc v. Trong khi , khong chnh l lp (hay cc lp) lm kiu cho gi tr thuc tnh kiu thc th. Rng buc FUZZY ONTOLOGY AND FUZZY OWL 15 | P a g eSVTH: Trn Thanh Ton Phm nh n Bc 7: To cc thc th cho lp. ylbccuicngkhplimtvnglpxydngOntology.Cngvicchnh lc ny l to thc th cho mi lp v gn gi tr cho cc thuc tnh. Nhn chung, cc thc th s to nn ni dung ca mt c s tri thc v l vn c quan tm trong lnh vc Web ng ngha. 1.8.Ngn ng Web Ontology (OWL). Web Ontology Language (OWL) l ngn ng nh du c s dng xut bn v chia s d liu s dng cc ontology trn Internet. OWL l mt b t vng m rng ca khung m t ti nguyn (RDF) v c k tha t ngn ng DAML+OIL Web ontology mt d n c h tr bi W3C. OWL biu din ngha ca cc thut ng trong cc t vng v mi lin h gia cc thut ng ny m bo ph hp vi qu trnh x l bi cc phn mm. OWLcxemnhlmtkthuttrngyucitchoSemanticWebtrong tng lai. OWL c thit k c bit cung cp mt cch thc thng dng trong vic x l ni dung thng tin ca Web. Ngn ng ny c k vng rng s cho php cc h thngmytnhcthccthaythchoconngi.VOWLcvitbiXML, cc thng tin OWL c th d dng trao i gia cc kiu h thng my tnh khc nhau, s dng cc h iu hnh v cc ngn ng ng dng khc nhau. Mc ch chnh ca OWL l s cung cp cc chun to ra mt nn tng qun l ti sn, tch hp mc doanh nghip v chia s cng nh ti s dng d liu trn Web. OWL c pht trin bi n c nhiu tin li biu din ngha v ng ngha hn so vi XML, RDF v RDFS, v v OWL ra i sau cc ngn ng ny, n c kh nng biu din cc ni dung m my c th biu din c trn Web. C php tru tngC php DLNg ngha ObjectProperty(R)RRI_ AI A I ObjectProperty(S inverseOf(R))R-(R-)I_AI A I Bng 1.1. Cc m t thuc tnh i tng OWL C php tru tngC php DLNg ngha Class(A) Class(owl:Thing) Class(owl:Nothing) A AI_ AI I =AI I =C intersectionOf(C1, C2, ...)C1C2(C1C2)I = C1I C2 I 16 | P a g e FUZZY ONTOLOGY AND FUZZY OWL GVHDThS. Trng Hi Bng unionOf(C1, C2, ...)C1C2(C1C2)I = C1I C2 I complementOf(C)C(C)I = AI\ C I oneOf(o1, o2, ...){o1}{o2}({o1}{o2})I = {o1I, o2I} restriction(R someValuesFrom(C)) restriction(R allValuesFrom(C)) restriction(R hasValue({o})) restriction(R minCardinality(m)) restriction(R maxCardinality(m)) -R.C R.C -R.{o} > mR s mR {xeAI |-y. e RI . yeCI} {xeAI | y. e RI yeCI} (-R.{o})I=(xeAI| eRI) {xeAI |(# y. e RI) > m} {xeAI |(# y. e RI) s m} Bng 1.2. Cc m t thuc tnh lp OWL C php tru tngC php DLNg ngha Class(A partial C1 ... Cn)A C1...CnAI _ C1I ... Cn I Class(A complete C1 ... Cn)A C1...CnAI = C1I ... Cn I EnumeratedClass(A o1 ... on)A {o1}...{o}nAI = {o1I, ..., on I} SubClassOf(C1,C2)C1 C2C1I _ C2I EquivalentClasses(C1...Cn)C1...CnC1I = ... = CnI DisjointClasses(C1 ...Cn)CiCj, (1si j v yi yj khng trong c trong A, thu c ABoxAi,j = [yi/yj]A t A bng vic thay th tng s kin ca yi bng yj. Hnh 2.6: Lut bin i ca thut ton tableau gii bi ton tha. Lut trong Hnh 2.6 c p dng cho mt tp hu hn cc ABox S nh sau: Ly mt phn t A ca S v thay th n bng mt ABox A', bng hai ABox A', A" hoc bng nhiu ABox Ai,j. T cc lut bin i ta c nhn xt: Gi s ta thu c S' t tp hu hn cc ABox S bng cch p dng mt lut bin i, th S l hp l khi v ch khi S' hp l. Gi s C0 l mt m t khi nim ALCN dng chun ph nh. S khng tn ti mt dy v hn vic p dng lut {(C0(x0))} S1 S2 ... Gi s A l mt ABox thuc Si vi i 1, th: -Vimicthxx0xuthintrongA,tacmtdyduynhtccvaitr R1,..., R( 1) v mt dy duy nht cc c th x1,...,x -1 m {R1(x0, x1), R2(x1 , x2),...,R(x-1,x)_A.Trongtrnghpnytanirngxxuthinmc trong A. -Nu C(x) A i vi c th x mc , th su vai tr cc i ca C b bao bisuvaitrccicaC0tri.Tngt,mccacthbtk trong A c bao bi i su vai tr cc i ca C0. -NuC(x)thucA,thClmtmtconcaC0.Tngt,slngcc khng nh khi nim khc nhau trn x c bao bi kch thc ca C0. -S cc vai tr k tip khc nhau ca x trong A (ngha l cc c th y m R(x,y) A) c bao bi tng s ln xut hin ccgii hn nh nht trongC0 cng vi s lng cc lng t tn ti khc nhau trong C0. Bt u bng {{Co(xo)}}, ta thu c tp ABox S'm khng cnp dng lut bin icnasaukhitacmtslnhuhnpdnglutbini.MtABoxA c gi l hon thin khi v ch khi khng cn lut bin i no p dng c na. Tnh 44 | P a g e FUZZY ONTOLOGY AND FUZZY OWL GVHDThS. Trng Hi Bng hplcatpABoxhonchnhcthcquytnhbngvictmccmuthun. ABox A cha mu thun khi v ch khi mt trong ba tnh hung sau xut hin: 1.{(x)} _ A vi mt s c th x; 2.{A(x), A(x)} _ A vi mt s c th x v mt s khi nim A; 3.{( n R)(x)} {R(x,yi)| 1 i n+1} {yi yj | 1 i < j n+1} _ A. Hin nhin, mt ABox m cha mu thun khng th hp l. Do , nu tt c ABox trong S' cha mu thun, th S' l khng hp l, v nh vy {C0(x0)} cng khng hp l. C0 khngtho.Tuynhin,numttrongccABoxhonchnhtrongS'khngcmu thun th S' l hp l. iu dn n {C0(x0)} hp l v nh vy th C0 tho mn. Mt ABox A hon chnh v khng xung t l mt m hnh. Cc lut s c p dng ln trn A cho n khi khng cn lut no c th p dng na.Ta gi y l qu trnh m rng A. Vic thc hin theo thut ton ny cho php ta thu c mt b khng nh y ca A l . Khi ta pht hin ra mu thun trong c ngha l A khng tho mn hay ni cch khc ta a ra c cu tr li cho cu hi rng C D l ng hay sai. kt thc phn ny, ta xt mt v d n gin, trong c s dng cc khi nim c a ra trong v d Hnh 3.2. V d: Chng minh rng Mother Parent Hay Mother (Mother Father) Lc ny ta ch xt mt TBox n gin l T = {Parent Father Mother} p dng lut de Morgan v lut - ta c dy bin i sau: Ah(Mother (Father Mother))(x)i hMother(x)i, h(Father Mother)(x)i hMother(x)i, hFather Mother)(x)i hMother(x)i, hFather(x)i, hMother(x)i Hnh 2.7: V d chng minh Mother Parent C th nhn thy rng mu thun xut hin gia hai khng nh hMother(x)i v hMother(x)i trong . iu chng t rng Mother Parent l ng. 2.5.M rng ngn ng m t FUZZY ONTOLOGY AND FUZZY OWL 45 | P a g eSVTH: Trn Thanh Ton Phm nh n trn ta c bit n ngn ng ALCN l mt ngn ng logic m t mu. i vi nhiungdng,khnngbiudincaALCNlkhngpngc.Vvy,nhiu constructormrngngnnglogiccara.Trongphnnytaxemxtcc m rng quan trng ca logic m t. l cc constructor mi c dng xy dng cc vai tr phc tp, ng thi ta cng tho lun v kh nng biu din ca cc gii hn s lng. 2.5.1.Cc constructor vai tr Khi cc vai tr c din dch ng ngha l cc quan h nh phn, ta c th dng cc tonttrnccquanhnhphn(nhtontbool,hpthnh,ovaitr)lmccconstructor thit lp cc vai tr. C php v ng ngha ca cc constructor ny c th c nh ngha nh sau: Tt c cc tn vai tr l mt m t vai tr (vai tr nguyn t), v nu R, S l cc m t vai tr, th R S (php giao), R S (php hp), R (php ph nh), R o S (php hp thnh),

(ovaitr)cnglccmtvaitr.MtdindchIchotrccm rng cho cc m t vai tr phc tp nh sau: 1.(R S)I = RI SI, (R S)I = RI SI, (R)I = AI AI \ RI; 2.(R o S)I = {(a,c) AI AI | b.(a,b) RI . (b,c) SI}; 3.(

)I = {(b,a) AI AI | (a,b) RI}. Chnghn,phphpcaccvaitrhasSonvhasDaughtercthcdng nh ngha vai tr hasChild, o vai tr ca hasChild em n vai tr hasParent 3.5.2.Biu din cc gii hn s Trc ht, ta c th xem xt cc gii hn s lng (qualified number restrictions) c lin quan n R-filler thuc v mt khi nim c th. V d, cho vai tr hasChild, ta c th biu din rng s lng ca ton b cc a tr b gii hn trong khong nht nh, nh trong khi nim 2 hasChild 5 hasChild. Gii hn s lng cng c dng biu din rng c t nht 2 con trai v nhiu nht 5 con gi nh sau: 2 hasChild.Male 5 hasChild.Female. Ngoi ra, ta c th thay th cc ch s tng minh trong gii hn s bng cc bin i din cho mt s nguyn bt k khng m. Chng hn, nh ngha khi nim tt c nhng ngi c t nht s con gi bng s con trai, m khng ni tng minh ngi ny c bao nhiu con trai v bao nhiu con gi: Person hasDaughter hasSon 46 | P a g e FUZZY ONTOLOGY AND FUZZY OWL GVHDThS. Trng Hi Bng 2.6.Tng kt chng Trong Chng 3 ta tho lun v nhng khi nim c bn ca logic m t v ngn ng truy vn c s tri thc Datalog. Cu th l:-Ngn ng ALC l ngn ng cho php ta xy dng nhng khi nim phc hp t nhng khi nim v vai tr nguyn thu. ALC l ngn ng chun, cc m rng ca ALC cung cp cho ngn ng c kh nng biu din linh hot hn. Cc constructorc dng m rng ALC l lng t tn ti (R), lng t vi mi (R), ton t phnh ( ), ton to vai tr () v cc lng t gii hn ( gii hn nh nht ( n), gii hn ln nht ( m) ). -CngvibiudincstrithcbngALCthngquaccTBoxvABox, ChngnycngtholunphpdindchIcdngxydngng ngha cho logic m t. -Chng ny cng cung cp cc dch v gi quyt cc bi ton c bn trn logic m t l bi ton tho, bi ton tng ng v bi ton giao CHNG 3. FUZZY ONTOLOGY AND FUZZY OWL.3.1.Logic m t m. 3.1.1.Gii thiu. Trong mt thp k qua c mt s lng ln cc cng vic c thc hinlin quan ti thuc tnh ca logic m t (Description Logics (DLs)) [18]. Logic m t l mt thitlplilogiccacigilngnngbiudintrithcframe-based,vimcch cungcpmtthitlpngincckhaibongnghakiuTaskinmbtngha ca cc tnh nng ph bin nht ca cu trc biu din ca tri thc. Ngynay,logicmttrnnphbindongdngcantrongSemanticweb. Semanticwebgnythuhtnhiuschcagiihcvinvnghnhcng nghip,vccoilbcphttrintiptheocaWorldWideWeb.Nnhmtng cng ni dung trn World Wide Web vi siu d liu, cho php cc tc nhn ( my mc hoc ngi s dng ) x l, chia x v gii thch ni dung Web.Ontology ngmt vai tr quan trng trong SemanticWeb. V chn vn nycn s n lc ln ca cng ng Semantic Web. Mt ontology bao gm mt m t phn cp cucckhinimquantrngtrongmtmincth,cngviccmtvthuctnh (trong cc trng hp) ca tng khi nim. Logic m t ng mt vai tr c bit trong trng hp ny v chng thuc l thuyt c bn ca Web Ontology Language OWL DL, FUZZY ONTOLOGY AND FUZZY OWL 47 | P a g eSVTH: Trn Thanh Ton Phm nh n kthututinngnngnhr(xcnh)ontologies.Saunidungwebc ch thch bng cch da vo cc khi nim c nh ngha trong mt min ontology c th. Tuy nhin, OWL DL tr nn t ph hp trong nhng trng hp m trong cc khi nim c biu din c nh ngha khng chnh xc. Nu chng ta a vo php tnh m chng ta phi gii quyt vi ni dung trang Web, sau ta d dng xc nh c rng kch bn ny l khng c kh nng thc hin. V d ch cn xt cc trng hp khi chng ta xy dng mt ontology v hoa. Khi chng ta s gp phi cc vn v cc miu t khinimnhCandiaisacreamywhiterosewithdarkpinkedgestothepetals,Jacarandaisahotpinkrose,Callaisaverylarge,longwhitefloweronthickstalks. R rang cc khi nim nh vy kh c th m ha thnh OWL DL, v cc khi nim m h nh creamy, dark, hot, large v thick khng th nh ngha r rang v chnh xc. Cc bi ton gii quyt cc khi nim khng chnh xc c a ra vi thp k trcybiZadeh,trongsinhracigiltpmvlthuyttpmvmts lng ln cc ng dng thc t tn ti trong i sng hng ngy. ng tic, tuy l thuyt tp m ngy cng c ph bin nhng khng c nhiu nghin cu m rng DLs i vi cc khi nim khng chnh xc, mc d DLs c xem l mt ngn ng kh dng m rng. TrongphnnychngtaxemxtmtphnmrngmcaSHOIN(D),ccDL tngngcaOWLDL(ontologydescriptionlanguage),cphpvngnghaca OWL DL. Tnh nng chnh ca fuzzy SHOIN(D) l n cho php biu din v suy lun v cc khi nim khng r rng. 3.1.2.C php v ng ngha ca logic m t m. 3.1.2.1.Ton t m. , , , v tng ng l mt t-norm, t-conorm, hm ph nh v hm ko theo; vi , e [0, 1] ta c: Lukasiewicz negation

1 - Go del t-norm

min{, } Lukasiewicz t-norm

max { + -1, 0} Go del t-conorm

max {, } Lukasiewicz t-conorm

min { + , 1} 48 | P a g e FUZZY ONTOLOGY AND FUZZY OWL GVHDThS. Trng Hi Bng php ko theo Go del

{

php ko theo Lukasiewicz

min {1, 1- + } php ko theo Kleene-Dienes

max {1 , } Bng 3.1. Ton t m 3.1.2.2.Concrete Fuzzy Concepts. Concrete Fuzzy Concepts (CFCs) xc nh tn cho mt tp m vi mt hm thuc m chi tit (gi s a b c d) (a)(b)(c) (d)(e)(f) Hnh 3.1. (a) Crisp value; (b) L-function; (c) R-function; (d) (b) Triangular function; (e) Trapezoidal function; (f) Linear hedge. (define-fuzzy-concept CFC crisp(k1,k2,a,b))crisp interval (hnh 3.1 (a)) (de_ne-fuzzy-concept CFC left-shoulder(k1,k2,a,b))left-shoulder function (hnh 3.1 (b)) (define-fuzzy-concept CFC right-shoulder(k1,k2,a,b))right-shoulder function (hnh 3.1(c)) (define-fuzzy-number CFC triangular(k1,k2,a,b,c))triangular function (hnh 3.1(d)) (define-fuzzy-concept CFC trapezoidal(k1,k2,a,b,c,d)) trapezoidal function (hnh 3.1(e)) 3.1.2.3.Fuzzy Numbers. Trc tin, nu fuzzy number c s dng, chng ta phi xc nh phm vi [k1, k2] _ nh sau: (define-fuzzy-number-range k1 k2). Cho fi l mt fuzzy number (ai, bi, ci) (a b c) v n e . FUZZY ONTOLOGY AND FUZZY OWL 49 | P a g eSVTH: Trn Thanh Ton Phm nh n namefuzzy number definitionname (a, b, c)fuzzy number(a, b, c) nreal number(n, n, n) (f + f1 f2 fn)addition(

,

,

) (f f1 f2)substraction(a1 c2, b1 b2, c1 a2) f* f1 f2 fnaddition(

,

,

) f/ f1 f2division(a1/c2, b1/b2, c1/a2) fuzzy number c th c gi l: (define-fuzzy-number name fuzzyNumberExpression) 3.1.2.4.Truth constants. Truth constants c th c xc nh nh sau (v sau ny,n c th s dng lm gii hndicamttinm):(de_ne-truth-constantconstantn),ynlmtgitr hp l trong [0, 1]. 3.1.2.5.Concept modifiers (b ng khi nim). modifiers thay i hm thuc ca mt khi nim m. (define-modifier CM linear-modi_er(b))linear hedge with b > 0 (hnh (f)) define-modifier CM triangular-modi_er(a,b,c))triangular function (hnh(d)) 3.1.2.6.Features (chc nng). cc chc nng c thuc tnh kiu d liu. (define-concrete-feature F *integer* k1 k2)The range is an integer number in [k1, k2] (define-concrete-feature F *real* k1 k2)The range is a rational number [k1, k2] (define-concrete-feature F *string*)The range is a string 3.1.2.7.Datatype restrictions (gii hn kiu d liu). (>= var F)at least datatype restriction

[FI (x, b) (b var)] (>= F f (F1,, Fn)at least datatype restriction

[FI (x, b) (b f (F1,, Fn)I )] (>= FN F)at least datatype restriction

[FI (x, b) (b

) FN I (

) (n T) | (sn T) | T1, , Tn.D | -T1, , Tn.D FUZZY ONTOLOGY AND FUZZY OWL 55 | P a g eSVTH: Trn Thanh Ton Phm nh n C D | {c1, , cn} V d, chng ta c th c khi nim: Flower (-hasPetalWidth.(>20mm s40mm)) -hasColour.Red) biu th tp hp cc loi hoa c cnh hoa trong khong 20mm n 40mm v cnh hoa c mu . y >20mm (v s40mm) l mt min c th. Chng ta c th s dng (= 1 S) biu din (> 1 S) ( s 1 S). (ii)Ng ngha. Mt din dch I i vi mt min c th D l mt cp I = (AI , .I) trong I L mt tp khc rng c phn chia t AD, mt hm dch .I ch nh cho mi C e C l mt tp con ca I.Vi mi R e Ra l tp con ca AI x AI , vi mi a e Ia l mi phn t trong AI, vi mi c e Ic l mt phn t trong AD, vi mi T e RC l tp con ca AI x AD. Hm dch .I m rng cho cc khi nim v vai tr nh sau: I=AI I= C (C1 C2)I=C1I C2I (C1 C2)I=C1IC2I (C)I=AI \ CI (

)I={(y, x): (x, y) e SI} (R.C)I={x e AI : RI(x) _ CI} (-R.C)I={x e AI : RI(x) CI # C} (> n S)I={x e AI : |SI(x) > n } (s n S)I={x e AI : |SI(x) s n } {a1, , an}I={a1I, , anI} Bng3.7 m rng cc khi nim trong SHOIN(D) V tng t cho cc cu trc khc, khi RI (x) = {y: (x, y) e RI} v |X| biu th cc yu t ca tp X. c bit, (-T1, , Tn.d)I = { x e AI : [TiI (x) TnI (x)] dD # C} Tnh hp l. Tnh hp l ca mt tin E trong mt din dch I = (AI , .I), k hiu I |= E, c nh ngha nh sau: I |= C D nu CI _ DI, I |= R S nu RI _ SI, I |= T U 56 | P a g e FUZZY ONTOLOGY AND FUZZY OWL GVHDThS. Trng Hi Bng nu TI _ UI, I |= trans(R) nu RI l chuyn tip, I |= a:C nu aI e CI, I |= (a, b):R nu (aI, bI) e RI, I |= (a, c):T nu (aI, cI) e TI, I |= a ~ b nu aI = bI, I |= a b nu aI = bI. Vi mt tp tin E, ta ni I tha mn E nu I tha mn mi phn t trong E. Nu I |= E ta c th ni I l mt m hnh ca E. I tha mn mt c s tri thc K = (T, R, A), k hiu l I |= K, nu I l mt m hnh cu thnh T ng vi R v A. Logicalconsequence(Hquhpl).MttinElmtLogicalconsequence ca mt c s stri thc K, k hiu l K |= E, nu mi thnh phn caK u tha mn E. Theo [15], s k tha v sp xp vn c th quy v c s tri thc tha mn vn . V D 3.1. Chng ta xem xt mt ontology n gin sau (TBox T) v Car vi RBox rng. Car (maker) (paenger) (peed) (= 1 maker) Car maker.Maker (= 1 passenger) Car passenger.N (= 1 speed) Car speed.km/h Roadster Cabrolet -passenger.{2} Cabriolet Car -topType.SoftTop SportCarCar -peed245km/h Trong T, gi tr cho tc c tnh bng gi tr c th kilomet trn gi (Km/h), trong khi gi tr cho passenger c tnh bng s t nhin, V ng >245km/h l biu din gi tr ln hn hoc bng 245km/h. ABox A cha cc khng nh sau y: Mgb:Roadster (-maker.{mg}) (-speed,170km/h) Enzo:Car (-maker.{ferrari}) (-speed,350km/h) tt:Car (-maker.{audi}) (-speed,243km/h) Xem xt cc c s tri thc K = (T, R, A). D dng xc nh c rng: K Roadster CarK mg:Maker K enzo:SportsCarK tt:SportsCar FUZZY ONTOLOGY AND FUZZY OWL 57 | P a g eSVTH: Trn Thanh Ton Phm nh n Vdtrnminhhamtkhkhntrongvicxcnhrrangccloixeththao. Tht vy, c mt nghi vn t ra l ti sao mt chic xe c tc 243km/h khng phi l mt chic xe th thao. V c bn, mt chicxe c tc cng cao cng c kh nng l mt chic xe th thao, v vy chng ta phi lm m khi nim v xe th thao thay v lm rchng.Trongphntiptheochngtasthylmthnolmchocckhinim thch hp hn. 3.1.3.2.2.logic m t m SHOIN (D). Tp m c gii thiu bi Zadeh [34] y l mt cch gii quyt cc khi nim m, khng r rang v d nh p sut thp, tc cao. Chnh thc, mt tp m A i vi mt tp X c trng bi hm thuc A : X [0, 1], quy cho mt thuc A, A(x), vi mi phn t x nm trong X. A(x) cho chng ta mt c lng v thuc ca x vi A. C th, nu A(x) = 1 th x chc chn thuc A, nu A(x) = 0,8 th x c kh nng l mt phn t ca A. (i)C php fuzzy SHOIN(D) Chng ta bit rng SHOIN (D) cho php suy lun vi cc loi d liu c th, chng hnnhccchuivsnguynbngcchsdngcigilconcretedomains.Trong phng phpm haca chng ta,concrete domains cth da trn cc tpml tt nht.Concrete fuzzy domain. Mt Concrete fuzzy domain l mt cp (AD,uD), trong AD l mt min din dch v uD l tp hp cc min thuc tnh c th d vi mt nh ngha trc arity n v mt din dch dD : A

[0, 1], l mt quan h m n-ary trn AD. Vd,iviSHOIN(D),ccvts18cthlmtthuctnhrtrntpst nhin, biu th tp hp cc s nguyn nh hn hoc bng 18 tc l s18 : Natural [0, 1] v s

() {ns n Nhvy,Minor=Person-age.s18(1),nhnghamtngictuinhhnhoc bng 18, tc l n nh ngha mt tr v thnh nin. Mt khc, v vic khng xc nh r r nt phm vi thuc tnh m, chng ta nh li rng trong l thuyt tpm v thc tin cnhiuhm thuc ca tpm nh r thnh phn. Tuy nhin, chng ta c Trapezoidal function, Triangular function; L-function , R-function 58 | P a g e FUZZY ONTOLOGY AND FUZZY OWL GVHDThS. Trng Hi Bng rt n gin v thng xuyn c s dng xc nh thuc. cc function trn xc nh trn tp s thc khng m R+{0}. Hnh 3.2. (a) Trapezoidal function; (b) Triangular function; (c) L-function; (d) R-function Trapezoidal function trz (x, a, b, c, d) c nh ngha nh sau: Cho a < b s c < d l s hu t th khi (xem hnh 1) (){

s ()() e , - e , -()() e ,c d- > Triangular function tri(x; a, b, c) c nh ngha: ( ){

s ()() e , -()() e ,b c- > Lu : tri(x; a, b, c) = trz(x; a, b, b, c). L-function c nh ngha l: FUZZY ONTOLOGY AND FUZZY OWL 59 | P a g eSVTH: Trn Thanh Ton Phm nh n () { s ()() e , - > Cui cng, R-function c nh ngha l: () { s ()() e , - > S dng cc function ny chng ta c th xc nh, v d: Young:Natural [0, 1] l mt thuc tnh m trn tp s t nhin biu th mc tr ca tui ngi. C th thuc tnh m Young c nh ngha l: Young(x) = L(x; 10; 30). Nh vy: YoungPerson = Person -age.Young (2), biu th mt ngi tr tui. Modifiers(b ngha). Chng ta c th s dng fuzzy modifiers (b ngha m) cho cc tp m thay i hm thuc ca chng. C th, mt modifier (b ngha) l mt hm fm: [0,1][1,0].Vd,chngtacthnhnghavery(x)=x3,trongkhinhngha slightly(x) = . V d, chng ta c th nh ngha khi nim xe th thao nh sau. SportsCar = Car -speed.very( High ), (3) y, very l mt khi nim modifier (b ngha), vi hm thuc very(x) = x2 v High l mt thuc tnh m c th c nh ngha l High(x) = R(x; 80, 250) TngtchngtacthphtbiunhnghaCallaisaverylarge,longwhite flower on thick stalks nh sau. Calla =Flower (-haSize.very(lage)) (-hasPetalWith.Long) (-hasColour.White) (-hasStalks.Thick) y, Large, Long v Thick l cc thuc tnh m. Tm li, c php ca fuzzy SHOIN(D) nh sau: C | | A | C1 C2 | C1 C2 | C | R.C | -R.C | (> n S) | (s n S) | {a1, , an} | (>n T) | (sn T) | T1, , Tn.D | -T1, , Tn.D C D | {c1, , cn} 60 | P a g e FUZZY ONTOLOGY AND FUZZY OWL GVHDThS. Trng Hi Bng RBoxm(FuzzyRBox).MtRBoxmRlmttphphuhncctinc tnhbccu(transitivity)trans(R)caSHOIN(D)vccvaitrmtinbaohm (fuzzy role inclusion axioms) dng ( > n), ( s n), ( > n) v ( < n), y ng vai tr l mt tin bao hm (role inclusion axioms) SHOIN(D). TBox m (Fuzzy TBox) mt TBox m T bao gm mt tp hu hn cc khi nim m tin bao hm (fuzzy concept inclusion Axioms) c dng ( > n), ( s n), ( > n) v ( < n) y l mt khi nim tin bao hm SHOIN(D). ABox m (Fuzzy ABox) mt ABox m A bao gm mt hu hn cc khi nim m v cc vai tr m tin khng nh (fuzzy role assertion axioms) c dng ( > n), ( s n), (>n)hoc( 0.1), ((a, b):R s 0.3), (R S > 0.4), hoc (C D s 0.6) l tin m. t quanimngngha,mttinm(sn)pgitrcanhhnhocbngn (tng t cho >, >, 0.2) Tc l, (Jim:Person -age.Young > 0.2), miu t Jim l mt YoungPerson vi mc t nhp l 0.2. Mt khc, mt khi nim m c tin dng: (C D > n). Biu th rng mc gp vo gia C v D t nht l n. C s tri thc m. mt c s tri thc m SHOIN(D) K = (T, R, A) gm c mt TBox m T, RBox m R v ABox m A. (ii)Ng ngha fuzzy SHOIN(D) Din dch m. Mt din dch m I i vi mt min c th D l mt cp I = (AI, .I) trong AI l mt tp khc rng c tch ta t AD, v .I l mt hm din gii (din dch) m n quy cho: -Mi khi nim tru tng (abstract concept) C e C l mt hm CI: AI [0, 1]; -Mi vai tr tru tng R e Ra l mt hm RI: AI AI [0, 1]; FUZZY ONTOLOGY AND FUZZY OWL 61 | P a g eSVTH: Trn Thanh Ton Phm nh n -Mi vai tr chc nng tru tng (hm thuc) R e Ra l mt hm cc b (mt b phn)RI:AIAI[0,1],nhvyvimixeAIcduynhtyeAIcnh ngha trong RI (x, y)-Mi tru tng ring bit (abstract individual) a e Ia l mt b phn trong AI; -Mi gi tr c th c e Ic l mt b phn trong AI; -Mi vai tr c th T e Rc l mt hm RI: : AI AD [0, 1]; -Mi vai tr chc nng c th T e Rc l mt phn chc nng tI:AI AD [0, 1], nh vy vi mi x e AI c duy nht v e AD c nh ngha trong TI(x, v); -Mi b ngha (modifier) m e M l mt hm fm: [0, 1] [0, 1]; -Mi n-ary c nh (concrete) thuc tnh m d trong mi quan h m dD:

[0, 1]. Hm din dch .I m rng cho cc khi nim v vai tr nh sau ( y x, y e AI, v e AD) : I (x)=1 I (x)=0 (C1 C2)I (x)=

(x) .

(x)(C1 C2)I (x)=

(x) v

(x)(C)I (x)=CI (x) (m(C))I (x)=fm(CI (x)) (R.C)I (x)=nf RI (x, y) CI (y) (-R.C)I (x) p RI (x, y) . CI (y) ( n S)I (x)= p*+ _

| *+|

SI (x, yi) ( n S)I (x)=( n + 1 S)I (x) {a1,, an}I (x)=

aiI = x d (v)=dD(v) {c1,, cn}I (x)=

ciI = v (T1,, Tn.D)I (x)= nf

(

(x, yi)) DI(y1,, yn) (-T1,, Tn.D)I (x)= p

(

(x, yi)) DI(y1,, yn) (

)I (x)=SI (y, x) Mt im ng quan tm ca ng ngha gii hn gi tr (> n), ng ngha ca khi nim (> n S): 62 | P a g e FUZZY ONTOLOGY AND FUZZY OWL GVHDThS. Trng Hi Bng ( n S)I (x)= p*+ _

| *+|

SI (x, yi) L kt qu ca s xem xt (> n S) c c t cng thc: -

( )

.

Nicchkhc,ctnhtnphntringbitpngmc(degree)S(x,yi)no . iu ny m bo rng -S.T (> 1 S). Ng ngha ca (> n S) c nh ngha nh vy m bo quan h c in (s n S) (> n + 1 S). Mt nh ngha thay th cho ( n S) v ( n S) c th da trn cu trc v hng ca cc yu t ca mt tp m. Saucng,dindch.Imrngchocctinkhngm(non-fuzzyaxioms)c quy nh trong bng sau ( y a,b e Ia): (R S)I=nf RI (x, y) SI (x, y) (T U)I=nf TI (x, y) UI (x, y) (C D)I=nf CI (x) DI (x) (a:C)I=CI (aI) ((a,b):R)I=RI (aI, bI). Lu , y khi nim ca tin bao hm C D da vo khi nim c suy lun trc tip t FOL(First Oder Logic), c dngx.FC(x) FD(x). nh ngha nymi l v r rang l khc vi phng php tip cn trong C D c xem nh l x.C(x) D(x). Cch tip cn ny nhm mc ch sp xp cc quan h thnh mt quan h c in {0, 1}. Tnh thc hin c (Satisfiability), khi nim tnh thc hin c ca tin E qua din dch m I , k hiu I |= E, c nh ngha nh sau: I |= trans(R), nu x,y e AI.RI (x, y) = eA RI (x, z) . RI (z, y). I |= ( n), y l mt (inclusion) bao hm c th hoc khi nim tin bao hm, nu I > n. Tng t, i vi cc quan h khc , < v >. I |= ( n), y l mt khi nim hoc mt khng nh ca tin nu I n. Tng t, i vi cc quan h khc , . Cui cng, I |= a ~ b nu aI = bI v I |= a b nu aI bI. FUZZY ONTOLOGY AND FUZZY OWL 63 | P a g eSVTH: Trn Thanh Ton Phm nh n i vimt tp tin E, ta ni I thamnE nu I thamnmiphn t trong E. Nu I |= E ta c th ni I l mt m hnh ca E. I tha mn mt c s tri thc K = (T, R, A), k hiu l I |= K, nu I l mt m hnh cu thnh T ng vi R v A. Logicalconsequence(Hquhpl).MttinElmtLogicalconsequence ca mt c s stri thc K, k hiu l K |= E, nu mi thnh phn caK u tha mn E. im th v theo ng ngha ny l, bng cch tham kho v d 1, mt mc nht nh chng ta s c tt l mt sport car. V vy khng ging trong v d 1, tt c kh nng l mt chic xe th thao. Hai v d sau s lm r nhng vn ny. V d 3.2: Chng ta thy v d 1, cc tin ca ABox v TBox c khng nh vimcl1,tclcdng(1).Chngtacththayiccnhnghaca SportsCar theo nh ngha (3) . Chng ta s c: K |= (SportsCar Car 1)K |= (enzo:SportsCar 1) K |= (mgb:SportsCar 0.25) K |= (tt:SportsCar 0,82). Lu l th no quy tc ca xe mbp (170km/h) vo mt gii hn ca thuc, trong v d trn l 0.25. V d 3.3. Xem xt cc c s tri thc K vi nh ngha (1) v (2). Sau , theo Lukasiewicz logic chng ta c: K |= (Minor YoungPerson 0.2) l mt quan h khng b rng buc bi SHOIN(D) c in. 3.1.3.2.3.Logic m t m SROIQ. TrongphnnychngtanhlinhnghacafuzzySROIQ[6],vimrng SROIQ n trng hp m bng cch cho php biu th nhng khi nim tp m ca c thvvaitrmbiuthmiquanhnhphn.Tincngcmrngchocc trng hp m . Chng ti nh ngha mc cc gi tr l mt s hu t dng o e [0, 1], | e [0, 1] v e [0, 1]. Hn na, chng ti nh ngha tp bt ng thc e {, }, e {, }. i vi mi ton t , chng ti nh ngha ton t i 64 | P a g e FUZZY ONTOLOGY AND FUZZY OWL GVHDThS. Trng Hi Bng xng

nhsau

=,

=;tontphnhcnh ngha nh sau = = , = >, < = . C php. Trong fuzzy SROIQ chng ti c 3 ch ci k hiu l khi nim (C), vai tr (R), v c th (I). Tp cc vai tr c xc nh bi RA U {

|R e RA}, trong RA e R, U l vai tr tng qut v

l nghch o ca R. Cho A e C, R, S e R ( y S l mt vai tr n gin [7]), oi e I cho I i m, m 1, n 0. Khi nim m c nh ngha tng qut nh sau: C,D | | A | C D |C D | C | R.C | -R.C | {1/o1, , m/om } | ( m S.C) | ( n S.C) | -S.Setf. vi a,b e I. Cc tin trong mt c s tri thc m K c nhm li trong mt ABox m A, mt TBox m T, v mt RBox m R1 nh sau:ABox Khi nim (a:C ), (a:C > ), (a:C ), (a:C < ) vai tr ((a, b):R ), ((a, b) : R > ), ((a, b) : R ), ((a, b) : R < ) Bt ng thc(a = b) ng thc(a = b) TBox Fuzzy GCI(C D ), (C D ) Khi nim trng uongC D, tng ng vi {(C D 1), (D C 1)} RBox Fuzzy RIA(R1, R2,, Rn R ), (R1, R2,, Rn R ) Vai tr c tnh bc cutrans(R) Vai tr phn chia (ri rc)dis(S1,S2) Vai tr c tnh phn x ref(R) Vai tr khng c tnh phn xirr(S) Vai tr c tnh i xngsym(R) Vai tr khng c tnh i xngasy(S) Bng 3.8 ABox, TBox v RBox trong SROIQ. Ng ngha: Mt din dch m I l mt cp (AI, .I) trong AI l mt tp khc rng v .I l mt din dch m n nh x: -Mi c th a thnh mt phn t aI ca AI; FUZZY ONTOLOGY AND FUZZY OWL 65 | P a g eSVTH: Trn Thanh Ton Phm nh n -Mi khi nim C thnh hm CI : AI [0, 1]; -Mi vai tr R thnhhm RI : AI AI [0, 1]; CI (hoc RI) biu th hm thuc ca khi nim m CI (hoc vai tr m R) i vi I. CI(x) (hoc RI(x, y))cho cng ta mc ca c th x - mt phn t ca khi nim m C (hoc (x, y) mt phn t ca vai tr m R) theo din dch m I. Cho mt t-norm , t-conorm , php nghch o v php ko theo [8], gii thch c m rng cho cc khi nim phc tp v vai tr nh sau: I (x) =1 I (x)=0 (C D) I (x)=CI (x) DI (x) (C D) I (x)=CI (x) DI (x) (C)I (x)=CI (x) (R.C)I=nf {RI (x, y) CI(y)} (-R.C)I=p {RI (x, y) CI(y)} {1/o1,, m/om }I (x)=p |

i

( m S.C)I (x)= p [(

{SI (x, yi) CI (yi)}) (j BA hoc AB A B 78 | P a g e FUZZY ONTOLOGY AND FUZZY OWL GVHDThS. Trng Hi Bng < /fowl:intersectionOf> < /fowl:Class> A B < /fowl:unionOf> < /fowl:Class> A < /fowl:complementOf> < /fowl:Class> -R.A < /fowl:Restriction> R.A < /fowl:Restriction> ( | )nR n< /fowl:cardType> < /fowl:Restriction>

< /fowl:ObjectProperty> -R.{x} < /fowL:Restriction> {x1,, xn} FUZZY ONTOLOGY AND FUZZY OWL 79 | P a g eSVTH: Trn Thanh Ton Phm nh n < /fowl:oneOf> < /fowl:Class> Bng 3.11: S Lng gii hn m. Tin mMinh ha bng OWL m A B ineqType < /fowl:Class> A B < /fowl:Class> Trans (R) Function(S) A(a) ineqType < /fowl:Thing> R(a, b) ineqType < /fowl:Thing> Bng 3.12: Tin m 80 | P a g e FUZZY ONTOLOGY AND FUZZY OWL GVHDThS. Trng Hi Bng Rng buc mMinh ha bng owL m R(c,d)* < /rdf:Description> Bng 3.13: Rng buc m Tip theo chng ti trnh by mt phn m rng ca OWL DL bng cch thm mc s kin OWL, chng ti gi l f-OWL. Nh cp trong phn 3.3.1, OWL lmt ngn ng ontology gn y c gii thiu bi W3C. Cng nh vi f-DLs, f-OWL, m rng tp trung vo s kin OWL (OWL facts). Dn n mt s kin m, v ng ngha ca ngn ng m rng. Vic m rng trc tip ng ngha m hnh l thuyt (model-theoretic semantics) ca f-OWL c cung cp bi mt din dch m, m trong thiu i cc kiu d liu v cc min c th. Mt din dchf-OWLcthcmrngcungcpngnghachokhinimm(fuzzy concept) vgi tr ring(individual-valued)m t c tnh. T tnh tng ng ca f-OWL m t mt lp [13] vi f-SHOIN l hin nhin, chng ti khng phi ni them v n y mt ln na. C th xem ng ngha ca chng trong [22] v trong phn 2. By gi chng ti mun tp trung vo ng ngha ca tin trong f-OWL. Chng s c tm tt trong bng 2. Chng ti mun ch ra rng nu b qua mt mc th mt tin ring tng ng vi quy nh c th c gi tr 1. T ng ngha quan im trn, mt tin f-OWL ca ct u tin ca bng 2tha mn bi mt din dch m I khi v ch khi phng trnh tngng ca ct thba l thamn. Mt ontologym O lmt tp cc tin ca f-OWL. Chng ti ni rng mt din dch m I l mt m hnh ca O khi v ch khi n tha mn tt c cc tin trong O. FUZZY ONTOLOGY AND FUZZY OWL 81 | P a g eSVTH: Trn Thanh Ton Phm nh n Bng 3.14: Tin ca fuzzy OWL. Mt s nhn xt v bng 3.14. Ng ngha ca mt min vmin gii hn c la chn cn thn cung cp mt gii thch trc quan trn min m v phm vi hn ch (min gii hn). Cui cng, ng ngha ca phn chia lp cho bi tin C D l tng ng vi quan h bao hm, C D T phng trnh m ny chng ti nhn ra rng a e AI .t(CI (a), DI (a)) I (a) = 0. Phng trnh ny phn nh trc gic ca chng ti km ri rc, m phi ni rng hai khi nim ch c phn chia khi v ch khi n khng c b ng chung trong bt k gii thch no. Hy nh rng s gii thch cho tin bao hm C D khng phi lun lun gi trong trng hp m. individual = Individual( [ individualID] {annotation} {type( type ) [membership]} {value [membership] } ) membership = ineqType degree ineqType= >= | > |